| /* |
| * Copyright (c) 2014 Google Inc. All rights reserved |
| * |
| * Permission is hereby granted, free of charge, to any person obtaining |
| * a copy of this software and associated documentation files |
| * (the "Software"), to deal in the Software without restriction, |
| * including without limitation the rights to use, copy, modify, merge, |
| * publish, distribute, sublicense, and/or sell copies of the Software, |
| * and to permit persons to whom the Software is furnished to do so, |
| * subject to the following conditions: |
| * |
| * The above copyright notice and this permission notice shall be |
| * included in all copies or substantial portions of the Software. |
| * |
| * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, |
| * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF |
| * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. |
| * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY |
| * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, |
| * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE |
| * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. |
| */ |
| #include <asm.h> |
| |
| .text |
| |
| FUNCTION(arch_spin_trylock) |
| mov x2, x0 |
| mov x1, #1 |
| ldaxr x0, [x2] |
| cbnz x0, 1f |
| stxr w0, x1, [x2] |
| 1: |
| ret |
| |
| FUNCTION(arch_spin_lock) |
| mov x1, #1 |
| sevl |
| 1: |
| wfe |
| ldaxr x2, [x0] |
| cbnz x2, 1b |
| stxr w2, x1, [x0] |
| cbnz w2, 1b |
| ret |
| |
| FUNCTION(arch_spin_unlock) |
| stlr xzr, [x0] |
| ret |